A treatment to reduce the risk of heart disease that combines a cholesterol lowering drug, drugs to reduce blood pressure and aspirin to reduce clotting may be tested in a major international trial in HIV-positive people within the next 18 months, Professor David Cooper of the National Centre in HIV Epidemiology and Clinical Research, University of New South Wales, Australia, said yesterday in Dublin.
The `polypill` has been proposed as a way of dramatically reducing the risk of heart disease by addressing the three main causes of cardiovascular events. Some researchers have advocated giving the pill to everyone over 55 years due to its low cost (approximately $20 a year) and its limited toxicity.
Speaking alongside Professor Cooper at the Seventh International Workshop on Adverse Drug Reactions and Lipodystrophy in HIV, in Dublin, Ireland, Dr Steve MacMahon of the George Institute for International Health, Sydney, said that a treatment which could reduce systolic blood pressure by 10-12 Hmmb, total cholesterol by 1mmol/l and provide a low dose anti-platelet treatment could reduce the risk of ischaemic heart disease by 50% and the risk of stroke by 60%. In smokers it could eventually cut the risk of stroke by 85% if the patient was also able to stop smoking and stay off cigarettes for life (the risk reduction effect of smoking cessation grows with time off cigarette smoking).
He also said that the thinking behind the `polypill` – attack the three strongest risk factors for heart disease – called into question the benefits of strategies targeting triglycerides, HDL cholesterol and blood glucose levels (all of which have featured strongly in the market differentiation strategies of pharmaceutical companies in the HIV field in recent years).
The international study of the `polypill` in HIV-positive people is being planned by the INSIGHT consortium, which combines two international trial networks (CPCRA and ESPRIT), and aims to recruit 8,000 patients if it receives funding. The trial was designed following the publication of results of the DAD study, a large international prospective study of cardiovascular risk factors and events in people receiving antiretroviral therapy.
However Dr Stephen Grinspoon of Massachusetts General Hospital cautioned against a one size fits all approach for HIV patients.
“If there’s one thing we’ve learnt in this population [as a result of studying the lipodystrophy syndrome] it is that there is heterogeneity. In addition, hypercholesterolaemia and hypertension are the two conditions [implicated in the metabolic syndrome] least seen in this population, and the drugs used for treating hypertension are not always benign, especially in the context of polypharmacy in HIV-positive people.”
However Dr Jens Lundgren said that only around 10% of the HIV-positive population would be eligible for such a study.